huatuo/bpf/hungtask.c

46 lines
1018 B
C

#include "vmlinux.h"
#include <bpf/bpf_core_read.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#include "bpf_common.h"
#include "bpf_ratelimit.h"
char __license[] SEC("license") = "Dual MIT/GPL";
#define CPU_NUM 128
BPF_RATELIMIT_IN_MAP(rate, 1, CPU_NUM * 10000, 0);
struct {
__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
__uint(key_size, sizeof(int));
__uint(value_size, sizeof(u32));
} hungtask_perf_events SEC(".maps");
struct hungtask_info {
int32_t pid;
char comm[COMPAT_TASK_COMM_LEN];
};
struct tracepoint_args {
unsigned long pad;
char comm[COMPAT_TASK_COMM_LEN];
int pid;
};
SEC("tracepoint/sched/sched_process_hang")
int tracepoint_sched_process_hang(struct tracepoint_args *ctx)
{
struct hungtask_info info = {};
if (bpf_ratelimited_in_map(ctx, rate))
return 0;
info.pid = ctx->pid;
bpf_probe_read_str(&info.comm, COMPAT_TASK_COMM_LEN, ctx->comm);
bpf_perf_event_output(ctx, &hungtask_perf_events,
COMPAT_BPF_F_CURRENT_CPU, &info, sizeof(info));
return 0;
}